The US state of Michigan is home to two types of lizards, nineteen types of snakes and eleven types of turtles, all members of the class Reptilia. Reptiles are found throughout Michigan, although the only venomous species, the eastern massasauga rattlesnake, is seen only in the Lower Peninsula. Reptiles are cold-blooded, and so usually pass the cold winters of Michigan in frost-free areas, such as burrows (for snakes and land-dwelling turtles) or the bottoms of lakes and streams (for water-dwelling turtles). Most reptiles in Michigan are protected by state law, but many are still at risk due to human encroachment on their habitats, the draining of wetlands and, in the case of snakes, indiscriminate killing by fearful humans. In 1995, the painted turtle was named as Michigan's state reptile